ES2221439T3 - GEL TYPE VAPOR RELEASE DEVICE. - Google Patents

Abstract

A device for the diffusion of a volatile ingredient, a device comprising a gel obtainable by mixing of: a) a hydrophilic medium; b) a volatile ingredient selected from the group consisting of a perfume, an insect repellent, a deodorant and a sanitary agent; and c) a synthetic organic polymer containing acrylic or methacrylic acid, or a salt thereof, said polymer being capable of absorbing between 50 and 200 times its own weight of hydrophilic solvent; said gel allowing diffusion of said volatile ingredient from the gel when the latter is exposed to air and being located in a container that is adjacent to a reservoir containing a hydrophilic solvent, providing means to ensure a continuous supply of the hydrophilic solvent to the gel to keep the said gel moistened.

Description

Type Vapor Release Device gel.

The present invention relates to the field of perfumery. It is, more particularly, a gel device that allows an efficient and prolonged evaporation of a substance volatile active, such as a perfume, an insect repellent or a deodorant or sanitary agent.

In recent years, they have been used increasingly diverse devices for diffusion of compounds volatile, for example perfumes, sanitary agents, repellents of Insects, and the like. For example, they are commonly used air fresheners or deodorants in almost every home both to mask bad smells and to perfume the air environment. In known devices used for broadcasting of Volatile compounds in the environment use several principles. As an example, the dispersing devices can be mentioned here Sprayer type, aerosols or mechanical type. Others Examples include plastic packaging elements that enclose the active ingredients in liquid form. Typically, diffusion of the active ingredient takes place through permeable membranes to the vapors of the mentioned ingredient.

A class of systems capable of spreading the volatile active ingredients are solid state devices consisting of solid materials or vehicles impregnated with a active ingredient. These devices may consist of various materials that are able to absorb the ingredient and to then release it more or less controlled. Between the Examples of these known materials include gels, such as agar-agar or sodium stearate gels, resins synthetic polymers, or blocks of mineral material, for example, cement or silica For some purposes, it is possible to still have the active ingredients absorbed on paper or cardboard in order to get a more or less solid vehicle device for broadcast of the volatile ingredient so absorbed. Often the solid devices are designated as non-humectants, that is, as capable of effectively retaining volatile active material liquid allowing only the diffusion of the aforementioned vapors material.

In general, broadcast devices have to Be activated by the consumer himself. These devices usually comprise a bag or sack containing the active ingredient and That is tightly closed. To release the ingredient, the user has to pinch the bag, blow it up or take off a part of it in order to let the active ingredient escape to the environment. Other devices comprise compartments multiple that have joints between them that are breakable, being at less one of these compartments of a material not permeable to ingredient vapors and the other being permeable. The devices of this class are activated by applying a pressure to non-permeable compartment, which opens the breakable gasket to let the active ingredient flow in the compartment that It is permeable to its vapors. A broadcast device of this class is that described in US Patent 4,798,288, for example. In the patents EP-A-0835666, WO-A-9818503 and US-A-4739928 are described devices for releasing volatile components, which are based on a gel Devices that are based on a wick system are described in FR-A-2 635 955, US-A-4915301 and US-A- 4739926.

Despite the known broadcast devices previously for volatile ingredients, there is still a need of broadcast devices that are capable of releasing quantities effective active ingredient to the environment, usually spaces closed, and this for a prolonged period of time.

Description of the invention

According to the invention, this object is achieved with a device for diffusion of a volatile active ingredient such as the one defined in claim 1.

The authors of the present invention have found that the diffusion systems according to the invention provide a very uniform and prolonged diffusion of the ingredient active.

As an active ingredient can be used, for For example, perfumes, with which air fresheners are obtained. Others suitable active ingredients comprise deodorant agents or sanitary ware, or insect repellents, or any other material volatile capable of imparting perceptible and desirable benefits to the air quality in which they are diffused.

The absorbent material according to the present invention, intended to be mixed with the hydrophilic medium, preferably an aqueous solution, emulsion or suspension of the volatile active ingredient, is a known material or substance as superabsorbent. These are materials capable of absorbing large amounts of water or other hydrophilic medium. In the context of the present invention, superabsorbents are organic polymers synthetics containing acrylic acid or methacrylic acid, or a salt from them, these polymers being able to absorb between approximately 50 and 200 times its own weight, of water or solvent hydrophilic Among the most common superabsorbents can be mentioned crosslinked sodium polyacrylate / poly acid polymers acrylic. The superabsorbents of this type are commercially available under the names of Salsorb® (Allied Colloids Ltd.) and Cabloc® (Stockhausen GmbH).

The superabsorbents of the invention, which are in the form of a fine powder, they will preferably have a size of particle of about 50 to about 500 microns with the in order to provide a uniform gel when mixing the components of the broadcast device You can also use powders with particle sizes larger or smaller than those mentioned, but will give rise, respectively, to thicker or thinner gels.

According to the invention, the best results have been obtained with crosslinked sodium polyacrylates sold under the trade name of Salsorb®.

The absorbent material, as it has been specified above, mixed with a hydrophilic solvent, preferably water or a water based medium that may contain a small amount of ethanol or similar solvent, and the volatile active ingredient. In general, the hydrophilic solvent It will contain the volatile active ingredient. For this purpose, it generally use a solution, suspension or emulsion of the active ingredient in said hydrophilic solvent.

The hydrophilic solvent is an essential element of the present invention. Your presence is essential for achieve the desired regular and prolonged evaporation of the ingredient active. It can be said that said solvent acts as a evaporation aid. Without the presence of solvent, the evaporation of the active ingredient usually takes place at a speed so low that an effective operation of the device according to the present invention. Another advantage is that it reaches a uniform distribution of the active ingredient in the Absorbent material.

When the said solution is prepared, suspension or emulsion, it may be advantageous to use an agent emulsifier, although this is optional. In general, a surfactant as emulsifying agent. Have been prepared systems that have resulted in satisfactory operation without use a surfactant, in which the volatile ingredient active, for example, perfume, and water are kept in suspension by the gel structure. When surfactants are used, nonionic surfactants are preferred. Between the examples of this class of surfactants include esters of ethoxylated sorbitan found under the names Span® (origin: ICI) and Brij® (origin: ICI). Can be also use ethoxylated saturated fatty esters such as sold under the names of Cremophor® (origin: BASF) and Lutensol® (origin: BASF). Other examples of nonionic surfactants Suitable include alcohol ethoxylates, polyethylene esters glycol and copolymers of ethylene oxide / propylene oxide. These surfactants may be present in solution, emulsion or aqueous suspension of the active ingredient in concentrations that range from 0 to 10% by weight, preferably from 1 to 3% by weight, with respect to the total weight of said resulting solution, emulsion or suspension.

As mentioned before, the ingredient asset that will be disseminated by the device of the invention can be typically a perfuming ingredient, a deodorant or an agent Sanitary or insect repellent.

As perfume or perfuming ingredient you can use in the device of the present invention any ingredient or mixture of ingredients used currently in perfumery. The latter may be formed for discrete chemicals; more frequently, however, it will be a more or less complex mixture of volatile ingredients from natural or synthetic origin. The nature of these ingredients is you can find in specialized perfume books, for example at S. Arctander (Perfume and Flavor Chemicals, Montclair N.J., USA 1969) or similar reference books, without justification Here a more detailed description of them.

Although special mention has been made here before of the perfuming effect that can be exerted by the device the invention, the same principles apply to the manufacture of similar devices for diffusion of deodorant vapors or sanitary, replacing the base perfume with a composition deodorant, a bactericide, an insecticide, a repellent of insects or even an attractant of insects. The term "steamers sanitary "refers not only to the vapors of substances that can enhance the degree of acceptance of the air that surrounds the observer, but also refers to substances that can exert an attractive or repellent effect on certain insect species, for example towards flies or mosquitoes, or also, that they can have bactericidal or bacteriostatic activity. Needless to say, mixtures of these can also be used Agents

The compounds identified above are administered with water or an appropriate hydrophilic solvent in a amount that may vary, for all types of gels, of about 0.1% to about 15% by weight of the solution, resulting emulsion or suspension, preferably about 1 at about 6% by weight. When using superabsorbents, these values may differ slightly from the previous ones that are valid for conventional absorbent media. The authors of this invention have found that quantities can also be employed older active ingredient. For superabsorbents of the type sodium polyacrylate polymer / acrylic polyacid, can reach values of approximately 0.1% to approximately 20% in weight of active ingredient in solution, emulsion or suspension resulting, the preferred range being about 1% at approximately 6% by weight. It is evident that in the case that use small amounts, such as 0.1%, the observed effect will almost always be a minor effect and the time of Device life will be considerably shorter. The limit higher for the amount of active ingredient that can be use, on the other hand, will be determined by the capacity of the absorbent material to absorb the solution.

The absorbent material and the solution, emulsion or suspension containing the active ingredient will be mixed together to form a gel device capable of releasing the ingredient. When a superabsorbent is used as absorbent material, it will be present in an amount of approximately 0.1% at about 15%, preferably about 2% to 5% with respect to the total weight of the resulting gel, the rest being the weight of the solution, emulsion or suspension containing the ingredient.

The gel obtained after mixing the material absorbent with the solution, suspension or hydrophilic emulsion that contains the active ingredient, diffuses the active ingredient of evenly and over a prolonged period of several weeks, unlike broadcast devices before known. In addition, the device may be provided with an indicator depleted when all the ingredient and material have been consumed Absorbent is formed by a superabsorbent substance. These superabsorbent materials (which before mixing are in shape of a fine powder), they contract from the gel form to reach a conglomerate of the particles originally present, at deplete the volatile active ingredient. The appearance of these materials can then be described as wet opaque crystals that stick to each other and the item spent so it is distinguished easily from the gel originally obtained by mixing the components mentioned before.

The endpoint warning is even more visible when a water-soluble dye is incorporated into the superabsorbent dry, that is, before mixing the latter with the solution, emulsion or suspension of the volatile ingredient with the medium hydrophilic Before device activation, the dye does not It is distinguishable from superabsorbent powder. When the superabsorbent containing the dye with the solution, emulsion or suspension of the active ingredient, the dye dye, as consequence of the presence of water and the distribution of the dye in the gel, thus providing the user with a clear indication that the broadcasting device is now activated. The presence of the dye also facilitates the recognition of the point end of the device, due to the change between the original gel and the particles that form when the diffusion device is exhausted. Another advantage of the presence of the dye is that the user can follow the process of mixing or activating the device of the invention with their own eyes thanks to the colored appearance. I only know they need small amounts of dye to get the effects desired, and typical concentrations are approximately 0.01% to about 1%, preferably 0.1% by weight, based on to the weight of the superabsorbent.

An advantage of the device of the invention is which, once sold out, can be refilled by simply adding emulsion or fresh solution containing an active ingredient at material already used The device will work in the same way good that a device that has been activated for the first time.

The activation of an air freshener device according to the present invention can be made of different ways.

In a preferred embodiment of the air freshener device according to the present invention, the said device comprises a reservoir containing a solvent appropriate hydrophilic. The gel is located in a container adjacent to the aforementioned deposit. The device carries means to ensure an appropriate supply of hydrophilic solvent to the gel. As the hydrophilic solvent, the same liquids as for the preparation of the solution, emulsion or suspension that It contains the active ingredient. The hydrophilic solvent plus Water is preferred.

Because of this, the gel will remain completely moistened by the liquid throughout its life, that is, until that all active compound has evaporated. As mentioned before, it has been found that the hydrophilic solvent, in particular water, acts as an evaporation aid for the ingredient active. A lower evaporation rate is observed for the cited active ingredient if the gel is not properly moistened, respectively hydrated, by a hydrophilic solvent, even if an amount of active ingredient remains in the gel that does not it would still result in elevation at said evaporation rate. Keeping the gel sufficiently moistened, it ensures a effective and complete evaporation of the active ingredient, and as result in a prolonged life of the air freshener.

The devices to provide a supply Appropriate hydrophilic solvent to gel are known for Any specialist in the art. For example, a possibility is to provide the aforementioned supply per capillary action. Frequently, simple capillaries or small tubes made, for example, of glass or plastics. The better results have been obtained, however, using a wick. Naturally, the material and dimensions of this wick will be of being chosen so that a sufficient amount of solvent to the gel to keep it completely moistened. The amount needed depends on the amount of gel and its absorbent properties

A large number of materials can be used Organic and inorganic for the wick. Among the examples of Appropriate inorganic materials include porcelain material porous, fiberglass, or asbestos, in combination with a suitable binder such as, for example, plaster or bentonite. It is also possible to prepare wicks of mineral powder materials, such as, for example, clay, talc, kieselgur, alumina, silica or the like, alone or in combination with, for example, sawdust, dust of carbon, or activated carbon, using an appropriate glue. Between Suitable organic materials include felt, cotton, pulp, woven and non-woven cotton fibers, synthetic fibers woven and non-woven, and porous polymeric foams and sponges

Advantageous results can be obtained with a wick consisting of a polyester fill surrounded by perforated polypropylene. This material is marketed by Baumgartner Papier SA, Switzerland.

The wick must be able to transport the solvent hydrophilic, usually water, to the gel, at least as quickly as the solvent evaporates from the gel surface.

As mentioned before, in this mode of realization of an air freshener according to the present invention, the gel it will be in a container adjacent to the tank and connected to it by an appropriate supplier, preferably a wick. It is preferable that the gel is seated on a piece of absorbent material connected to the wick, such as thick absorbent paper, for example, filter paper, in order to ensure a regular distribution of the solvent in the gel.

The container that collects the gel carries a cover of a material that is permeable to the vapors of active ingredient, in order to prevent the gel from falling out. For this purpose a mesh can be used.

Vapor permeable material is sealed with an appropriate closure that can be easily opened by the user after your purchase, in order to activate the device of the air freshener according to the present invention.

In this preferred embodiment of a air freshener according to the present invention, it is possible to add simply new water to the tank once it is empty, in as long as active ingredient remains in the gel. For this, it is It is possible, for example, to incorporate larger amounts of perfume into gel and provide an air freshener device with a shelf life prolonged in which the deposit has to be simply occasionally filled in by the user to maintain the device in operation.

After activation, the device gel of diffusion of the invention will preferably have a surface of evaporation from about 10 to about 60 cm2, preferably from about 20 to about 40 cm2, to allow effective diffusion of the active ingredient.

The device of the present invention allows a linear and effective perfume release, with only small amounts of perfume in the gel after depletion of the perfume or the other active ingredient.

The invention will be described below with more detail by way of the following examples.

Brief description of the drawings

Figure 1 represents the weight loss, in function of time, of two gels according to the invention, in comparison with that of conventional carrageenan gel.

Figure 2 shows the amount of perfume emitted by a wick type air freshener according to the invention, comparing with the amount of the same perfume emitted by an aqueous gel polyurethane pre-polymer, depending on the weather.

Figure 3 shows the results obtained from a test panel of the intensity of the perfume emitted from the two gels identified above, as a function of time.

Figure 4 shows an embodiment of a wick type air freshener according to the present invention. A deposit 1 filled with a liquid, preferably water, a wick 2 that provides the liquid feeding medium to gel 4 located in the top of the device and keeps it wet. The gel is sits on a piece of filter paper 3 or other capable material of absorbing the liquid and ensuring a regular humidification of the gel.

Examples Example 1

Perfume compositions were prepared by mixing of the following ingredients, in various proportions within the indicated intervals.

Ingredients Intervals of concentrations percentages in weight Dipropylene Glycol fifty - 70 Isobornyl acetate 5 - twenty Terpineol fifteen Oil of eucalyptus 0.2 - 3 Methyl nonyl aldehyde 0.2 - 3 Dihydromyrcenol one - 8 Terpinyl acetate 0.5 - 5

Using any of the perfumes as well obtained, air fresheners according to the invention were prepared with the following ingredients, in the indicated proportions:

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Ingredient % in weigh gel \ underline {Gel one} \ underline {Gel 2} \ underline {Gel 3} Water deionized 92 89 95 Fragrance 3 6 3 Agent non-ionic surfactant 3 3 - - Salsorb® two two two Colorant water soluble * trace trace - - * Green D \ textamp C No. 5 of D.F. Anstead Ltd. UK

The typical Salsorb * containing 0.1% of its weight of uniformly distributed water-soluble dye inside it to the previously prepared emulsion of the perfume (3% of the total emulsion) in water containing the surfactant (3% of the total emulsion), which had been placed in a container of glass, for example a small bottle or a size bottle appropriate. When mixed, a very soft gel formed immediately that remained firm in the jar even if the latter was given the return.

Similar gels can be obtained in containers of plastic of any form that is desired, that when settling as a gel, it can be covered with a grid that allows evaporation of the perfume contained in the gel.

Figure 1 shows the evolution over time of the weight loss suffered by two gels according to the invention (gels 1 and 2 above) as the perfume evaporates, in comparison with the behavior of a conventional air freshener that commercially available and based on a conventional gel of carrageenan containing 3% by weight of perfume. This Figure shows it follows that the gels of the invention consistently release a greater amount of perfume / water in the same period of time. The gel intensity test and head space analysis consistently shows that the scented is more intense and with Enhanced release of perfume components, compared with Conventional gels

Example 2

Scented compositions were used according to those described in Example 1 to prepare an air freshener Wick type with a water tank and Salsorb * as material absorbent. 80 g were used to which 5 g of fragrance. 2% by weight of Salsorb * was used. Perfume level emanating from the wick system over 4 weeks was compared with the level of perfume that emanated from an aqueous gel of polyurethane pre-polymer containing the same perfume in identical quantity, for an analysis of the spaces of SPME type heads (Micro solid phase extraction). The results are shown in Figure 2, which clearly illustrates that the wick type air freshener according to the present invention releases an almost constant amount of perfume during the 4 weeks. The air freshener based on pre-polymer polyurethane releases too much perfume beginning, amount that falls rapidly to low levels after a few weeks.

These results were confirmed by a panel of semi-experts who classified the intensity of perfume emitted by both devices after 1, 2, 3 and 4 weeks on a scale of 1 to 7. The results are shown in the Figure 3. The panel results clearly confirm that the Polyurethane type air freshener gives an intense aroma right away from the activation, which falls, however, stationary with the weather. The wick type air freshener according to the present invention, on the other hand, provides practically a smell constant over 4 weeks.

Claims (21)

1. A device for the diffusion of a volatile ingredient, device comprising an obtainable gel by mixing of:

to)

a hydrophilic medium;

b)

a volatile ingredient selected from the group consisting of a perfume, an insect repellent, a deodorant and an agent sanitary; Y

c)

a synthetic organic polymer containing acrylic acid or methacrylic, or a salt thereof, said polymer being capable to absorb between 50 and 200 times its own solvent weight hydrophilic;

allowing said gel the diffusion of said volatile ingredient from the gel to be the latter exposed to air and being located in a container which is adjacent to a reservoir containing a hydrophilic solvent, providing means to ensure a continuous supply of the hydrophilic solvent to the gel to keep the aforementioned so dampened gel. 2. A device according to claim 1, characterized in that the gel is placed on a piece of absorbent material connected to the wick. 3. A device according to claim 1, characterized in that the hydrophilic solvent is water or a water-based solvent. 4. A device according to claim 1, characterized in that the hydrophilic medium is water or water-based solvent, and that said medium is in the form of a solution, emulsion or suspension with said volatile ingredient. 5. The device according to any of the preceding claims, characterized in that the polymer is selected from the group consisting of polymers containing acrylic acid or methacrylic acid or a salt thereof, polyacrylamides, polyacrylic esters, polymethacrylic esters, copolymers of acrylates, methacrylates, Acrylic or methacrylic acid with vinyl acetate, vinyl alcohol or maleic anhydride, isobutylene-maleic anhydride copolymers, saponified acrylonitrile graft polymers and starch and acrylic acid graft polymers. 6. The device according to claim 5, characterized in that the polymer is a crosslinked sodium polyacrylate polymer / poly acrylic acid. 7. The device according to claim 6, characterized in that the polymer is a powder having a particle size of about 50 to about 500 microns. The device according to claim 4 to 7, characterized in that said solution, emulsion or suspension of the volatile ingredient comprises an emulsifying agent. 9. The device according to claim 8, characterized in that said emulsifying agent is a non-ionic surfactant, present in an amount of approximately 10% by weight, based on the total weight of said solution, emulsion or suspension. 10. The device according to any of the preceding claims, characterized in that the volatile ingredient is present in the solution, emulsion or suspension in an amount of about 0.1% to about 15% by weight of the solution. 11. The device according to claim 10, characterized in that the polymer is a substance of the sodium polyacrylate / poly acrylic acid type and the amount of volatile ingredient in the solution, emulsion or suspension is from about 0.1% to about 10% in solution weight. 12. The device according to claim 11, characterized in that the amount of volatile ingredient in solution, emulsion or suspension is from about 1% to about 6% by weight of the solution. 13. The device according to any of the preceding claims, characterized in that the polymer is of the sodium poly acrylate / poly acrylic acid type and is present in an amount of about 0.1% to about 15%, based on the total weight of the gel obtained after mixing the ingredients. 14. The device according to claim 13, characterized in that the polymer is present in an amount of about 2% to about 5% by weight, based on the total weight of the gel obtained after mixing the ingredients. 15. The device according to any of the preceding claims, characterized in that the polymer contains from about 0.01% to about 1% by weight of a water-soluble dye. 16. A device according to any of the preceding claims, characterized in that a wick is provided to ensure the supply of hydrophilic solvent to the gel. 17. A device according to claim 16, characterized in that the wick is formed by an inorganic material selected from the group consisting of porous porcelain materials, glass fibers, and asbestos, in combination with a binder, and pulverized mineral materials, alone or in combination with sawdust, carbon powder, or activated carbon, using a glue, or is formed of an organic material selected from the group consisting of felt, cotton, pulp, woven and non-woven cotton fibers, woven and non-woven synthetic fibers -wovens, and porous polymeric foams and sponges. 18. A device according to claim 17, characterized in that the wick is formed of polyester surrounded by perforated polypropylene. 19. A device according to any of the preceding claims, characterized in that the reservoir containing the gel is covered by a material that is permeable to the vapors of the active ingredient and that can be closed with a removable closure. 20. The device according to any of the preceding claims, characterized in that the gel resulting from the mixture of the hydrophilic medium, the volatile ingredient and the polymer has an evaporation surface of about 10 to about 60 cm 2. 21. The device according to claim 20, characterized in that said gel has an evaporation surface of approximately 20 to 40 cm 2.